diff --git a/drivers/ethernet/phy/phy_microchip_ksz8081.c b/drivers/ethernet/phy/phy_microchip_ksz8081.c
index a3d753d7b7d..61a97ca03e7 100644
--- a/drivers/ethernet/phy/phy_microchip_ksz8081.c
+++ b/drivers/ethernet/phy/phy_microchip_ksz8081.c
@@ -26,6 +26,8 @@ LOG_MODULE_REGISTER(LOG_MODULE_NAME);
 #define PHY_MC_KSZ8081_OMSO_REG			0x16
 #define PHY_MC_KSZ8081_OMSO_FACTORY_MODE_MASK	BIT(15)
 #define PHY_MC_KSZ8081_OMSO_NAND_TREE_MASK	BIT(5)
+#define PHY_MC_KSZ8081_OMSO_RMII_OVERRIDE_MASK	BIT(1)
+#define PHY_MC_KSZ8081_OMSO_MII_OVERRIDE_MASK	BIT(0)
 
 #define PHY_MC_KSZ8081_CTRL2_REG		0x1F
 #define PHY_MC_KSZ8081_CTRL2_REF_CLK_SEL	BIT(7)
@@ -235,6 +237,10 @@ static int phy_mc_ksz8081_static_cfg(const struct device *dev)
 
 	omso &= ~PHY_MC_KSZ8081_OMSO_FACTORY_MODE_MASK &
 		~PHY_MC_KSZ8081_OMSO_NAND_TREE_MASK;
+	if (config->phy_iface == KSZ8081_RMII) {
+		omso &= ~PHY_MC_KSZ8081_OMSO_MII_OVERRIDE_MASK;
+		omso |= PHY_MC_KSZ8081_OMSO_RMII_OVERRIDE_MASK;
+	}
 
 	ret = phy_mc_ksz8081_write(dev, PHY_MC_KSZ8081_OMSO_REG, (uint32_t)omso);
 	if (ret) {